1248262 九、發明說明： 【發明所屬之技術領域】 本發明係有關於硬體没計領域，特別係指一種用於無線通訊之電路系 統0 【先前技術】 無線區域網路(wirelessLAN，以下簡稱WLAN)為一種藉由無線電訊號 而使通訊不受舰束缚的行動式網路，愈來愈多的家庭及企業開始利用 WLAN，而其技術的創新則幫助人們在工作和溝通上更有效率。高度移動 性、無需纔線及其它固定的基礎建設所帶來的好處已證明了令許多的使用 者艾^良夕WLAN的使用者仍然可以如同在乙太(趾咖过)區域網路中運 用相同的網路魏。筆或桌上龍翻的WLAN配接卡所支援的網路 協定和乙太網路配接卡-樣，對錄使时而言，除了新增加的肌顧移 動性優點之外，絲的6太晴制與行献的紙颜讀狀間並沒有 顯著的功能上差異。 電機和電子工程師協會(以下簡稱正EE)於西元1997年採用並公布了第 =…線乙太、鹏;^準’即丨8G211，這個統—的標準提供了數種運作模式 且貝料速率最大可達每秒2百萬位元(2 。ieee沒多久便開始著手改 ^ 的效此因而產生兩個新的、卻不相容的版本：802.11a及802.11b， b版本 = 斤運作的頻率範圍與原始的8〇2 ιι 一樣是在以億赫兹以卿的 a <頻贡仁a版本則運作於％億赫兹(5 〇出)的卩棚頻帶。8021化明 ^ 4馬技術以達到5·5和丨1 Mbps的速率，還包含了可選用的 PBCC編碼技術，能尤《《1 此在5.5和Π Mbps的資料速率範圍提供更遠的連線距 離：8〇^a轉而軸多載波調變技術，稱為正交分頻多讀術(0FDM)， ,、最大广料傳輸速率可達^―坪。西元湖年$月，正现宣佈了縱⑽ 、/ W版本獅^準採用混合的解決方案，包含了相同的〇fdM技術 075l-A30287TWF(5.0) 1248262 且提供和8G2.11a -樣的實體資料速率，但是謝㈣然使用原始8〇2 ΐι 標準的2.4 GHz頻帶。 任何的祕若含有射頻(radiGfreqUeney，以下簡稱剛的訊號，其電路 設計將會是—概_顧。#龍傳輸速率增加時，會造餅刷電路板 的佈局更形複雜’尤其是那些小型化裝置，如··符合8G211a/b/g標準的 施啦《PCMCIA卡，為獲取這些裝置所能提供的最大利益，就必須特 別注意電路上易受高頻影響的性質。一個不符合要求的設計會造成机颜 裝置的技術缺失’而顯現出連線覆蓋範圍減小、資料傳輸速率下降的問題， 有鑑於此’歪需-種適用於_系統的電路設計，以克服上述的問題及 習知技術的缺點。 【發明内容】 本發明係針對-種無線通訊電路系統，其經由第―、第二天線收發射 頻(RF)訊號。根據本發a月，該電路系統包括一印刷電路板，其上具有未塗佈 防焊材料之既定區域，而天線切換裝置、第—舰裝置以及功率放大^ 關鍵的RF前端(front-end)零件則須安裝在該印刷電路板之該既定區域内。 天線切換裝置具有至少二輸入埠及至少二輸出埠，其能使該些輸出璋兩者 之一與任一輸入埠互相連接，而該些輸出埠分別耦接於上述第一、第二天 線，第-渡波裝置麵接至該天線切換裝置的其中一個輸人璋，肖以將來自 於第-或第二天線之RF接收訊號中的誠頻率成份祕於該第一據 波裝置以及-收發器之間的第-匹配電路則將該处接收訊號從單端型式 變成差動型式；為透過RF前端把訊號發送出去，則以機裝置把基頻發送 訊號從數位型式變成類比型式，且於該轉換裝置及該收發器之間轉接一第 二濾波裝置，錢雜換裝置之細阻抗和職發器之輪人阻抗相匹配； 該收發器負責將該灯接收訊號降頻成為基_接收訊號，亦將該基頻的發 送訊號升頻成為RF發送訊號；_於發如及該轉放大器之間的^ 0751-A30287TWF(5.0) 6 1248262 二匹配電路將該Rp發送訊號從差動型式變成單端型式 第二匹配電路相#於接收路徑上的該第一匹配電路；工;1248262 IX. Description of the Invention: [Technical Field] The present invention relates to the field of hardware, particularly to a circuit system for wireless communication. [Prior Art] Wireless LAN (hereinafter referred to as WLAN) As a mobile network that uses communications to keep communications unbound, more and more homes and businesses are starting to use WLANs, and their technological innovations help people work and communicate more efficiently. The benefits of high mobility, no-line and other fixed infrastructure have proven that many users of Ai Liang Xi WLAN can still use it in the Internet of Ethernet (toe). The same network Wei. The network protocol supported by the WLAN adapter card on the pen or table, and the Ethernet adapter card-like, in addition to the newly added muscle mobility advantages, the silk 6 is too There is no significant functional difference between the clear and the paper-reading patterns. The Institute of Electrical and Electronics Engineers (hereinafter referred to as EE) adopted and published the first line in 1997, Eto, Peng, and the standard of 8G211, which provides several modes of operation and feed rate. Up to 2 million bits per second (2. ieee did not take long to start changing the effect of ^ and thus produced two new, but incompatible versions: 802.11a and 802.11b, b version = kg operation The frequency range is the same as the original 8〇2 ι, which is in the 卩 频带 band of the billion Hz 频 频 频 以 以 。 。 。 。 。 802 802 802 802 802 802 802 802 802 802 802 802 802 802 802 802 802 802 802 802 802 802 802 Up to 5·5 and 丨1 Mbps, it also includes the optional PBCC encoding technology, which can provide a farther connection distance in the data rate range of 5.5 and Mbps Mbps: 8〇^a Axis multi-carrier modulation technology, called orthogonal frequency division multiple reading (0FDM), , the maximum wide material transmission rate can reach ^ ping. West Lake year $ month, is now announced the vertical (10), / W version of the lion ^ Quasi-mixed solution, including the same 〇fdM technology 0751-A30287TWF (5.0) 1248262 and provides 8G2.11a-like entities Data rate, but thank you (4) for using the original 2.4 GHz band of the standard 8 〇 2 ΐ ι. Any secret containing radio frequency (radiGfreqUeney, hereinafter referred to as the signal, its circuit design will be - _ _ Gu. #龙 transmission rate increased At the same time, the layout of the cake circuit board will be more complicated', especially those miniaturized devices, such as the PCGIA card that meets the 8G211a/b/g standard, in order to obtain the maximum benefit of these devices, Special attention must be paid to the nature of the circuit that is susceptible to high frequency effects. A design that does not meet the requirements will result in a lack of technology for the device, which shows a problem of reduced wiring coverage and reduced data transmission rate. There is a need for a circuit design suitable for the _ system to overcome the above problems and the disadvantages of the prior art. SUMMARY OF THE INVENTION The present invention is directed to a wireless communication circuit system that transmits and receives radio frequencies via the first and second antennas ( RF) signal. According to the present month, the circuit system includes a printed circuit board having a predetermined area of uncoated solder resist material, and the antenna switching device and the first ship device are Power amplification ^ The key RF front-end part must be mounted in the predetermined area of the printed circuit board. The antenna switching device has at least two input ports and at least two output ports, which enable the outputs to be both One of the input ports is connected to the first and second antennas, and the first wave device is connected to one of the input devices of the antenna switching device. The frequency component of the RF receiving signal of the first or second antenna is secreted by the first data matching device and the first matching circuit between the transceivers to change the receiving signal from the single-ended type to the differential type In order to transmit the signal through the RF front end, the base device transmits the fundamental frequency transmission signal from the digital type to the analog type, and switches a second filtering device between the conversion device and the transceiver. The fine impedance matches the wheel's impedance of the hairdresser; the transceiver is responsible for down-converting the lamp receiving signal into a base_receiving signal, and also up-converting the fundamental frequency transmission signal into an RF transmission signal; The amplifier Between ^ 0751-A30287TWF (5.0) 6 1248262 the two matching circuits into a single-ended signal transmission Rp second pattern matching circuit pattern from the differential phase # 2 to the receive path of the first matching circuit; workers;
=電路各自具有-制端點以及—對差動端點，並且包括··連接在該共同 該對差動端點中之第—端點間的第—電容；連接在該對差動端點 :之該第1點以及地線間的第—電感；連接在該共同端點以及該對差動 知點中之弟二端點間的第二電感，·連接在該對差動端點中之該第 卜％型式，而發送路徑上的該 電路；功率放大器則耦接於 匹配電路之間，將通過該第 L放大，藉此讓該RF發送訊號通過該天線切換裝 、第二天線發送出去。其中，上述第一、第二匹 及該地線_第二餘；財跨接在賴絲端狀紅並聯於該收發器 的可调式電感。 根據本發_另_要點，提出_種無顧湖之電路祕，其包括一 印刷，路板，板上具有未塗佈防焊材料之既定區域，而濾波裝置以及功率 放大器等j鍵的RF前端零件麵安裝在該印刷電路板之該既定區域内。遽 ^裝置負。責將濾除RF接收訊號中的無用頻率成份;麵接於該渡波裝置以及 -收發器之_第-眺電路則將該处接收訊號從單端型式變成差動型 弋、該^發态負貝將該处接收訊號降頻成為基頻的接收訊號，亦將基頻的 發送訊號升戦為RP發送峨；減於魏發旨以及該辨放大器之間的 第二匹配電路賴RF發送織從差翻式魏單端赋；該辨放大器則 把通過該第一匹配電路之好發送訊號予以適度地放大。其中，上述第一、 第二匹配電路各自具有—共同端點以及一對差動端點，並且包括··連接在 該共同端誠及該親動端財之第一端關的第_電容；連接在該對差 動端點中之該第-端點以及地制的第m接在該朗端點以及該 對差動、點中之弟一端點間的第二電感；連接在該對差動端點中之該第二 端點以及該地線間的第二電容；還有跨接在該對差動端點之間且並聯於該 收發器的可調式電感。 0751-A30287TWF(5.0) 7 1248262 印刷嫌七梅;，其包括- 波裝置以及功率放大器__ :：!之既^域’而天線切換裝置、攄 該既定區域内。天板之 用以將來_-衫===_«⑽卜_入璋’ 放大一天“置：_:== 以適度地放大，藉此讓該Rp私、矣㈣、s 將好1相號予 述第一、第：天線發送‘過該天線切換裝置之後，足以從上 【實施方式】 為使本發明之上述目的、特徵和優職更簡碰，下文特舉一較佳 實施例，並配合所附圖式，作詳細說明如下： 至於說明書騎赋’熟f此技藝者#綱瞭麟實際纽完整實施所需 之70件均給予介域顯示，而是只㈣些對徹絲解本發撕需之元件才 做詳述和圖解，此外，傳統的元件或可以根據此處提供的教示便能容易地 設計及製造的裝置亦不做詳述。 首先’全織日膨斤指的“實補”躲徵—種贿所有實補相關的特 徵、結構或躲，岐錄徵、輯雜性包含於本發·至少—實施例 中，因此在說明書裡不同地方所出現的“實施例，，一詞並不需要參考相同的實 施例，再者，那些特徵、結構或特性可能在一或多個實施例中組合而產生。 第1圖所示係根據本發明;^電路系統方塊圖，該電路系統可使一主電 腦(圖中未示)擁有802.lla的無線上網能力。本發明之電路系統耦接至兩支 (i~不限於)天線i〇2a、i〇2b來獲致空間分送(diversity)的效果，5 qhz頻帶 0751-A30287TWF(5.0) 8 1248262 Ί 上的RF接收和發送訊號係經過天線切換裝置1〇4而由天線l〇2a、丨㈣予 以收發。如圖示，天線切換裝置104具有四個埠··兩個輸出埠(天線端)以及 兩個輸入埠(發送和接收），其中，天線102a、1〇2b分別耦接於那兩個輸出 埠，而天線切換裝置104能讓其輸出埠的兩者之一與它的任一輸入埠互相 連接。帶通(bandpass)濾波器(簡稱BPF)106耦接至天線切換裝置1〇4的其中 一個輸入埠，藉以選取5 GHz附近之頻帶並且將來自於天線1〇2a或1〇2b 之RF接收訊號中的無用頻率成份濾除。本發明電路系統中的接收和發送路 徑上分別使用了匹配電路l〇8a、l〇8b，藉以將訊號從單端型式變成差動型 式或仗差動型式變成早端型式；在5 GHz的接收訊號進入收發器 (tranSceiver)ll〇之前，匹配電路10如於接收路徑上先將該訊號從單端型式 變成差動型式’換言之’單端型式的接收訊號通過匹配電路1〇^後，轉變 成差動型式的訊號RX一RF+ ' RX-RF—，兩者相位差為180。。收發器110 負責將訊號RX一RF+、RX一RF—從5 GHz的頻帶降頻到基頻帶(baseband)， 為省去中頻(intermediate frequency，IF)及基頻濾波器的需求，收發器n〇 以Zer〇_IF的架構為較佳。基頻接收訊號含有同相(ilH)hase)及正交(quadrature) 成份：RX一I和RX_Q，且訊號RX—I、RX—Q都設計成差動型式，當然這僅 僅是範例，本發明的實施例不會侷限於此。訊號RXj、RX_Q接著通過類 比-數位轉換器(簡稱ADC)122a和122b而到達所有前端訊號的起源及月的 地，即：基頻處理器120。IEEE 802· 11a標準所需的資料格式、封裝及解封 裝等過程係由基頻處理器120所執行，並且基頻處理器120還擔負與主電 腦溝通的介面。 發送訊號係以相反的順序從基頻處理器120透過天線切換裝置1〇4而 傳遞到天線102a或l〇2b。基頻處理器120的同相、正交輸出會到數位_ 類比轉換器(簡稱DAC)116a和116b，其中每個DAC均可將基頻的訊號從 數位型式變成類比型式。除此之外，為使各數位-類比轉換器之輸出阻抗和 收發器no之輸入阻抗相匹配，獨立的低通濾波器（簡稱LPF)118a$ 118b 0751-A30287TWF(5.0) 9 1248262 ϊ 分別耦接於收發器110以及數位-類比轉換器116a、H6b之間，其中濾波器 118a及118b係運作於基頻且具備低通濾波的特性。接下來，基頻發送訊號 的同相及正交成份TX—I和TX一Q則是進入到電路系統的rf前端部分，先 由收發器110將發送訊號TX一I、TX一q從基頻帶升頻到5(}1^的頻帶，在 本實施例中，來自於基頻處理器12〇的訊號TXJ[、tx_q均設計成差動型 式’當然這僅僅是範例，本發明的實施例並不會侷限於此。在5 GHz的訊 號TX—RF+、TX—RF—進入功率放大器112之前，匹配電路1〇肋先將發送 訊號從差動型式變成單端型式。功率放大器(簡稱PA)112耦接於天線切換 裝置104的另一個輸入埠以及匹配電路1〇8b之間，通過匹配電路1〇肋的 RF發送訊號由功率放大器112予以適度放大，致使处發送訊號通過天線 切換裝置104後，足以從天線102&或1〇2b發送出去。 上述收發器110其RF輸入部分需要外在的阻抗匹配(impedance matching)且必須進行單端型式到差動型式的轉換，而其妳輸出部分亦需要 外在的阻抗匹配且必須進行差動型式到單端型式的轉換；差動轉單端(或是 單鈿轉差動)以及阻抗匹配則是利用上述匹配電路1〇%和1〇8b來達成。第 2圖所示係匹配電路的實施例，根據本發明，各匹配電路可由被動元件的組 合來構成，如圖示，每個匹配電路具有一共同端點2〇1以及一對差動端點 203a、203b，共同端點201係用來耦接單端型式的訊號源或負載，而差動 端點203a、203b則係用來柄接差動型式的訊號源或負載，以第i圖的電路 系統為例，匹配電路l〇8a的共同端點輕接於帶通濾波器1〇6的輸出，而它 的-對差動端點則輕接於收發器110的好輸入端。第2圖顯示匹配電路包 括兩個電感li、L2以及兩個電容C1、C2而形成—個LC/CL電路網。電容 C1係連接在共同端點2〇1以及差動端點難之間；電感u係連接在差動 端點203b以及地線(grc)und)之間；另一方面，電感L2係連接在共同端點2〇1 以及差動端點203a之間；電容C2係連接在差動端點她以及地線之間。 再者，匹配電路還含有跨接在該對差動端點施和膽之間且並聯於收 0751-A30287TWF(5.0) ' 1248262 發盗110的可調式電感Lp，藉此使收發器HO的差動輸出或輸入阻抗得到 精確的匹配。然第2圖所舉僅僅是匹配電路之範例，本發明的實施例不會 侷限於此。 包含在本發明電路系統的上述收發器、基頻處理器及其他周邊的元件 均是安裝在印刷電路板300之上，由於阻抗匹配不良會降低發送功率和接 收敏感度，因此必須特別注意印刷電路板3〇〇的設計與佈局。一般而言， 印刷電路板上的訊號導線之阻抗與印刷電路板其基板(substrate)之介電常數 與整體厚度息息相關’而普通的FR4基板對這兩個參數的控制卻是不佳， 很有可能造成實際的阻抗值與預期的有所偏差，儘管如此，透過嚴格的阻 抗控制，印刷電路板300仍然是以普遍且便宜的FR4基板來製成。第3圖 所示係印刷電路板300之截面圖，其僅用於圖示說明，故只顯示部分並且 尺寸未按比例繪製，如圖示，印刷電路板3〇〇由4層銅箔ΜμΜ4以及3層 FR4基板S1-S4所構成，因為FR4絕緣材料的厚度、介電常數以及即前端 訊號導線的寬度會雜抗產生重大的影響，所以這些均是阻抗能否匹配最 為關鍵的因素。在較佳實施例中，FR4基板的S1和S3兩層之厚度皆是9 密爾(1密爾=千分之一英吋），FR4基板的S2層之厚度則是16密爾，而印 刷電路板300的全部厚度τ約等於40密爾；佈建於印刷電路板3〇〇上且耦 接於天線切換裝置、帶通濾波器、功率放大器、匹配電路以及收發器之間 屬於RF刖、訊號導線其線寬如苐3圖所標示為w，其中w=l6.5士 1.5密爾。 再者，RF前端船虎導線之間會加入接地平面(gr_dplane)來減少浪漏效應 及增強隔絕效果，第3圖亦顯示這些訊號導線和接地平面之間的間隔為〇， 其中G至少需達到15密爾。一般印刷電路板的正、反均會塗上防焊材料形 成防焊層⑽dermask)，本發明特地方在於··印刷電路板3〇〇上刻意形 成一塊未塗佈防焊材料之區域，並且必須將天線切換裝置、帶通濾波器以 及功率放大器安裝在這塊未塗佈防焊材料的既定區域之内，藉城格控制 電路系統在關鍵RF前端部分達到正確的阻抗。 0751-A30287TWF(5.0) π 1248262 第4圖所示係根據本發明另一實施例之電路系統方塊圖，該電路系統 提供802.1 la/b/g的無線上網能力。為說明簡潔起見，第4圖和第1圖中相 同或類似的元件將不再詳細描述。第4圖的雙頻電路系統耦接至天線4〇2a、 402b，而這兩支天線皆能在2.4〇]32和5 01^的頻帶運作，5〇112的接收 訊號從天線402a、402b兩者其中之一通過天線切換裝置4〇4、雙工器 (diplexei*)405、帶通濾波器406a以及匹配電路408a而傳遞至收發器410 ; 2.4 GHz的接收訊號以類似的方式從天線4〇2a或402b通過天線切換裝置 404、雙工态405、帶通濾波器406b以及匹配電路408c而傳遞至收發器410。 另一方面，5 GHz的發送訊號從雙頻收發器41〇經由匹配電路4〇8b、功率 放大器412a、雙工器415以及天線切換裝置404傳遞至天線4〇2a或402b ; 2.4 GHz的發送訊號則是從收發器41〇經由匹配電路4〇8d、帶通滤波器 414、功率放大姦412b、雙工器415以及天線切換裝置404傳遞至天線402a 或402b。本實施例中的功率放大器412a係運作在5 GHz附近的頻帶、而功 率放大器412b則係運作在2·4 GHz附近的頻帶。雙工器405和415各具有 一個天線端的共用埠以及分別給5 (^與么‘ _使用的埠，這兩個雙工 器在共用埠和5 GHz埠之間以5 GHz訊號的觀點來看如同是透明不存在， 同樣地以2.4 GHz訊號的觀點來看，雙工器4〇5和415於共用埠和2.4 GHz 埠之間亦是通透的。在2·4 GHz發送訊號行經路徑上，帶通濾波器414是用 來去除收發器410裡5 GHz壓控振盪器所產生的附帶成份。如前面所述， 天線切換裝置404、雙工器405和415、帶通濾波器406a和406b以及功率 放大器412a和412b都必須安裝在印刷電路板上未塗佈防焊材料的既定區 域之内，而該印刷電路反則同第3圖所示。第4圖的雙頻電路系統其基頻 部分和第1圖中的類似，包括了基頻處理器420、類比_數位轉換器422&和 422b、數位-類比轉換器416a和416b以及低通濾波器418a和418b，其中 IEEE802.Ua/b/g標準所需的資料格式、封裝及解封裝等過程係由基頻處理 器420所執行。 0751-A30287TWF(5.0) 12 1248262 练合以上所述’本發明揭露了一種電路系統，適用於8〇211a/b/g之類 的無線通訊顧，本發明的電路纟統不僅克服了習知技術的_，還提供 了具有成本效益的解決方式。 雖然本發明已以一具體實施例揭露如上，然其僅為了易於說明本發明 之技術内容，而並非將本發明狹義地限定於該實施例，任何熟習此技藝者， 在不脫離本發明之精神和範圍内，當可作些許之更動與潤飾，因此本發明 之保護範圍當視後附之申請專利範圍所界定者為準。 【圖式簡單說明】 第1圖是根據本發明實施例之無線通訊電路系統方塊圖； 第2圖是第1圖中所示匹配電路根據本發明實施例之詳細電路圖； 第3圖是根據本發明實施例之多層印刷電路板截面圖；以及 第4圖是根據本發明另一實施例之無線通訊電路系統方塊圖。 【主要元件符號說明】 102a-b、402a-b〜天線； 106、406a-b〜濾波裝置； 110、410〜收發器； 116a-b、416a-b〜數位-類比轉換器 118a-b、418a-b〜濾波裝置； 120、420〜基頻處理器； 405、415〜雙工器；The circuits each have an endpoint and a pair of differential endpoints, and include a first capacitor connected between the first endpoints of the pair of differential endpoints; connected to the pair of differential endpoints : the first point and the first inductance between the ground lines; a second inductance connected between the common end point and the second end of the pair of differential points, connected in the pair of differential terminals The circuit of the second type, and the circuit on the transmission path; the power amplifier is coupled between the matching circuits, and will be amplified by the L, thereby allowing the RF transmission signal to pass through the antenna switching device and the second antenna. Send it out. Wherein, the first and second horses and the ground line _ second balance; the crossover is connected to the tunable inductor of the transceiver in parallel with the red end. According to the present invention, it is proposed to use a printed circuit board, a board with a predetermined area of uncoated solder resist material, and a filter device and a power amplifier such as a j-key RF. The front end part face is mounted in the predetermined area of the printed circuit board.遽 ^The device is negative. It is responsible for filtering out the unwanted frequency components in the RF receiving signal; the _th-thing circuit connected to the wave device and the transceiver changes the receiving signal from the single-ended type to the differential type, and the negative state The beacon reduces the received signal to the received signal of the fundamental frequency, and also upgrades the transmission signal of the fundamental frequency to the RP transmission 峨; minus the second matching circuit between Wei Wei and the identification amplifier. The differential flip type Wei single-end assignment; the discrimination amplifier moderately amplifies the good transmission signal through the first matching circuit. The first and second matching circuits respectively have a common endpoint and a pair of differential endpoints, and include a _ capacitor connected to the first end of the common terminal. a second inductance connected between the first endpoint of the pair of differential endpoints and the mth of the ground and the endpoint of the pair of differentials and points; connected to the pair of differences The second terminal in the active terminal and the second capacitance between the ground lines; and a tunable inductor connected across the pair of differential terminals and connected in parallel to the transceiver. 0751-A30287TWF(5.0) 7 1248262 Printed the seven plums; it includes the -wave device and the power amplifier __::! and the antenna switching device, 摅 within the predetermined area. The use of the sky is for the future _-shirt ===_«(10) Bu_入璋' Amplify the day "set: _:== to moderately enlarge, so that the Rp private, 矣 (four), s will be a good phase number After the first and the first antennas are transmitted 'passing the antenna switching device, it is sufficient from above. In order to make the above objects, features and superior functions of the present invention more simple, a preferred embodiment is exemplified below, and With the reference to the drawings, the detailed description is as follows: As for the instructional riding, the skill of the craftsman is #熟了麟, the actual implementation of the complete 70 is given to the media, but only (four) The required components are detailed and illustrated. In addition, conventional components or devices that can be easily designed and manufactured according to the teachings provided herein are not described in detail. "Hidden levy - the characteristics, structure or hiding of all the stipulations of bribery, 岐 征 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 Words do not need to refer to the same embodiment, and further, those features, structures or special Example possible combinations generated at one or more. Figure 1 is a block diagram of a circuit system that allows a host computer (not shown) to have 802.11a wireless Internet capabilities in accordance with the present invention. The circuit system of the present invention is coupled to two (i ~ not limited to) antennas i 〇 2a, i 〇 2b to achieve spatial diversity, 5 qhz band 0751-A30287TWF (5.0) 8 1248262 上 RF The receiving and transmitting signals are transmitted and received by the antennas 1〇2a and 丨(4) via the antenna switching device 1〇4. As shown, the antenna switching device 104 has four ports (two antennas) and two input ports (transmitting and receiving), wherein the antennas 102a and 1b are respectively coupled to the two outputs. And the antenna switching device 104 can have one of its output ports interconnected with any of its inputs. A bandpass filter (abbreviated as BPF) 106 is coupled to one of the input ports of the antenna switching device 1〇4 to select a frequency band around 5 GHz and to receive an RF receiving signal from the antenna 1〇2a or 1〇2b. The unwanted frequency components in the filter are filtered out. The matching circuits l8a, l8b are respectively used in the receiving and transmitting paths in the circuit system of the present invention, thereby changing the signal from a single-ended type to a differential type or a differential type to an early type; receiving at 5 GHz Before the signal enters the transceiver (tranSceiver), the matching circuit 10 first converts the signal from the single-ended type to the differential type, in other words, the single-ended type receiving signal is passed through the matching circuit 1 to the receiving path. The differential type signal RX-RF+ 'RX-RF-, the phase difference between the two is 180. . The transceiver 110 is responsible for down-converting the signals RX-RF+, RX-RF-from the 5 GHz band to the baseband, in order to eliminate the need for intermediate frequency (IF) and baseband filters, the transceiver n The architecture of Zer〇_IF is preferred. The fundamental frequency receiving signal includes an in-phase (ilH)hase and quadrature components: RX-I and RX_Q, and the signals RX-I, RX-Q are all designed as a differential type, of course, this is merely an example, the present invention The embodiment is not limited to this. The signals RXj, RX_Q then pass through the analog-to-digital converters (ADCs) 122a and 122b to the origin of all front-end signals and the land of the month, namely the baseband processor 120. The data format, encapsulation, and decapsulation required by the IEEE 802.11a standard are performed by the baseband processor 120, and the baseband processor 120 is also responsible for communicating with the host computer. The transmission signals are transmitted from the baseband processor 120 through the antenna switching device 1〇4 to the antenna 102a or l〇2b in reverse order. The in-phase, quadrature outputs of the baseband processor 120 are passed to digital-to-analog converters (DACs) 116a and 116b, each of which can change the fundamental frequency signal from a digital version to an analog type. In addition, in order to match the output impedance of each digital-to-analog converter with the input impedance of the transceiver no, the independent low-pass filter (LPF) 118a$ 118b 0751-A30287TWF(5.0) 9 1248262 分别 respectively coupled Connected between the transceiver 110 and the digital-to-analog converters 116a, H6b, wherein the filters 118a and 118b operate at a fundamental frequency and have low-pass filtering characteristics. Next, the in-phase and quadrature components TX-I and TX-Q of the baseband transmit signal enter the rf front-end portion of the circuit system. The transceiver 110 first transmits the transmit signals TX-I and TX-q from the baseband. In the frequency band of 5 (}1^, in the present embodiment, the signal TXJ [, tx_q from the baseband processor 12" is designed to be a differential type. Of course, this is merely an example, and the embodiment of the present invention is not It will be limited to this. Before the 5 GHz signal TX-RF+, TX-RF- enters the power amplifier 112, the matching circuit 1 first changes the transmission signal from the differential type to the single-ended type. The power amplifier (referred to as PA) 112 coupling Connected between the other input port of the antenna switching device 104 and the matching circuit 1 8b, the RF transmission signal through the matching circuit 1 rib is moderately amplified by the power amplifier 112, so that after the signal is transmitted through the antenna switching device 104, It is transmitted from the antenna 102 & or 1 〇 2b. The RF input portion of the transceiver 110 requires external impedance matching and must be converted from a single-ended type to a differential type, and the output portion of the transceiver 110 also needs to be external. I'm here Anti-matching and the need to perform differential to single-ended conversion; differential to single-ended (or single-turn differential) and impedance matching are achieved using the above matching circuits 1〇% and 1〇8b. The figure shows an embodiment of a matching circuit. According to the present invention, each matching circuit can be constituted by a combination of passive components. As shown, each matching circuit has a common terminal 2〇1 and a pair of differential terminals 203a, 203b, the common end point 201 is used to couple the single-ended type of signal source or load, and the differential end points 203a, 203b are used to handle the differential type of signal source or load, and the circuit system of the i-th figure For example, the common end of the matching circuit 10a is lightly connected to the output of the band pass filter 1〇6, and its -to-differential end is lightly connected to the good input of the transceiver 110. Figure 2 shows The matching circuit includes two inductors li, L2 and two capacitors C1, C2 to form an LC/CL circuit network. The capacitor C1 is connected between the common terminal 2〇1 and the differential end point; the inductor u is connected. Between the differential terminal 203b and the ground line (grc) und); on the other hand, the inductor L2 is connected at the common terminal And a differential between the endpoints 203a 2〇1; capacitor C2 is connected between the differential lines and the ground her endpoint. Furthermore, the matching circuit further includes a tunable inductor Lp spanning between the pair of differential terminals and parallel to the receiving 0751-A30287TWF(5.0) ' 1248262 thief 110, thereby making the difference of the transceiver HO The dynamic output or input impedance is accurately matched. However, the second embodiment is merely an example of a matching circuit, and the embodiment of the present invention is not limited thereto. The above-mentioned transceiver, baseband processor and other peripheral components included in the circuit system of the present invention are mounted on the printed circuit board 300. Since the impedance matching is poor, the transmission power and the reception sensitivity are lowered, so special attention must be paid to the printed circuit. The design and layout of the board. In general, the impedance of the signal conductor on the printed circuit board is closely related to the dielectric constant of the substrate of the printed circuit board and the overall thickness. The control of these two parameters by the common FR4 substrate is not good. It is possible that the actual impedance value deviates from what is expected. However, through strict impedance control, the printed circuit board 300 is still made of a universal and inexpensive FR4 substrate. Figure 3 is a cross-sectional view of a printed circuit board 300, which is for illustration only, so that only portions are shown and the dimensions are not drawn to scale. As shown, the printed circuit board 3 is made of 4 layers of copper foil ΜμΜ4 and The three-layer FR4 substrate S1-S4 is composed. Since the thickness, dielectric constant, and width of the front-end signal conductor of the FR4 insulating material have a significant influence on the hybrid resistance, these are the most critical factors for matching the impedance. In the preferred embodiment, the thickness of both layers S1 and S3 of the FR4 substrate is 9 mils (1 mil = one thousandth of an inch), and the thickness of the S2 layer of the FR4 substrate is 16 mils, and printing The total thickness τ of the circuit board 300 is approximately equal to 40 mils; it is built on the printed circuit board 3 且 and is coupled to the antenna switching device, the band pass filter, the power amplifier, the matching circuit, and the transceiver. The signal conductor has a line width as indicated by 苐3 in the figure of w, where w = l6.5 ± 1.5 mils. Furthermore, a ground plane (gr_dplane) is added between the RF front-end ship's wires to reduce the leakage effect and enhance the isolation effect. Figure 3 also shows that the interval between these signal wires and the ground plane is 〇, where G needs to be at least 15 mils. Generally, the printed circuit board is coated with a solder resist material to form a solder mask (10) dermask. The special feature of the present invention lies in that the printed circuit board 3 is intentionally formed with an uncoated solder resist material region and must be The antenna switching device, the bandpass filter, and the power amplifier are mounted within a predetermined area of the uncoated solder mask material, and the correct impedance is achieved at the critical RF front end portion by the grid control circuitry. 0751-A30287TWF(5.0) π 1248262 FIG. 4 is a block diagram of a circuit system according to another embodiment of the present invention, which provides 802.1 la/b/g wireless Internet access capability. For the sake of brevity, the same or similar elements in Fig. 4 and Fig. 1 will not be described in detail. The dual-frequency circuit system of FIG. 4 is coupled to the antennas 4〇2a, 402b, and both antennas can operate in the frequency bands of 2.4〇]32 and 5 01^, and the receiving signals of the 5〇112 are from the antennas 402a and 402b. One of them is transmitted to the transceiver 410 through the antenna switching device 4〇4, the duplexer 405, the bandpass filter 406a, and the matching circuit 408a; the 2.4 GHz received signal is similarly transmitted from the antenna 4〇 2a or 402b is passed to the transceiver 410 via the antenna switching device 404, the duplex state 405, the bandpass filter 406b, and the matching circuit 408c. On the other hand, the 5 GHz transmission signal is transmitted from the dual-band transceiver 41 to the antenna 4〇2a or 402b via the matching circuit 4〇8b, the power amplifier 412a, the duplexer 415, and the antenna switching device 404; the 2.4 GHz transmission signal Then, it is transmitted from the transceiver 41 to the antenna 402a or 402b via the matching circuit 4〇8d, the band pass filter 414, the power amplifier 412b, the duplexer 415, and the antenna switching device 404. The power amplifier 412a in this embodiment operates in a frequency band around 5 GHz, while the power amplifier 412b operates in a frequency band around 2.4 GHz. Duplexers 405 and 415 each have a shared 埠 at the antenna end and 埠 used for 5 (^ and _', which are 5 GHz between the shared 埠 and 5 GHz 的As if the transparency does not exist, the duplexers 4〇5 and 415 are also transparent between the shared 埠 and 2.4 GHz 观点 from the point of view of the 2.4 GHz signal. The signal path is transmitted at 2.4 GHz. The bandpass filter 414 is used to remove the incidental components produced by the 5 GHz voltage controlled oscillator in the transceiver 410. As previously described, the antenna switching device 404, the duplexers 405 and 415, the bandpass filters 406a and 406b And the power amplifiers 412a and 412b must be mounted within a predetermined area of the printed circuit board that is not coated with the solder resist material, and the printed circuit is the same as shown in Fig. 3. The fundamental frequency portion of the dual frequency circuit system of Fig. 4 Similar to FIG. 1, a baseband processor 420, analog-to-bit converters 422 & 422b, digital-to-analog converters 416a and 416b, and low pass filters 418a and 418b, including IEEE 802.Ua/b/, are included. The data format, packaging, and decapsulation required for the g standard are based on The processor 420 performs the following: 0751-A30287TWF(5.0) 12 1248262 The above description discloses a circuit system suitable for a wireless communication device such as 8〇211a/b/g, and the circuit system of the present invention. The invention has not only overcome the conventional technology, but also provides a cost-effective solution. Although the present invention has been disclosed above in a specific embodiment, it is merely for ease of description of the technical content of the present invention, and the present invention is not narrowly defined. It is to be understood that the scope of the present invention is defined by the scope of the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a wireless communication circuit system according to an embodiment of the present invention; FIG. 2 is a detailed circuit diagram of a matching circuit shown in FIG. 1 according to an embodiment of the present invention; A cross-sectional view of a multilayer printed circuit board according to an embodiment of the present invention; and a fourth block diagram of a wireless communication circuit system according to another embodiment of the present invention. 102a-b, 402a-b~antenna; 106, 406a-b~filtering means; 110,410~ transceiver; 116a-b, 416a-b~digit-to-digital converter 118a-b, 418a-b~filtering device 120, 420~ baseband processor; 405, 415~ duplexer;
Cl、C2〜電容；Cl, C2~ capacitor;
Lp〜可調式電感； M1-M4〜銅箔層； W〜訊號導線寬度； 104、404〜天線切換裝置； 108a-b、408a-d〜匹配電路； 112、412a-b〜功率放大器； 122a-b、422a-b〜類比_數位轉換器； 300〜印刷電路板； 414〜帶通濾波器； LI、L2〜電感； S1-S3〜FR4基板層； T〜印刷電路板總厚度； 0751-A30287TWF(5.0) 13 1248262 G〜訊號導線與接地平面之間隔寬度。 0751-A30287TWF(5.0) 14Lp~ adjustable inductor; M1-M4~ copper foil layer; W~signal wire width; 104, 404~ antenna switching device; 108a-b, 408a-d~ matching circuit; 112, 412a-b~ power amplifier; 122a- b, 422a-b~ analog_digital converter; 300~ printed circuit board; 414~ bandpass filter; LI, L2~ inductor; S1-S3~FR4 substrate layer; T~ total thickness of printed circuit board; 0751-A30287TWF (5.0) 13 1248262 G~ The width of the signal conductor and the ground plane. 0751-A30287TWF(5.0) 14